Non-contact positions sensors are desirable because they have lower failure rates than traditional potentiometers. However, using a Hall Effect sensor as a non-contact position sensor requires a particular input polarity. In an embodiment, a polarity insensitive Hall Effect sensor includes conversion sensors configured to produce outputs responsive to an input. The sensor also includes a semiconductor rectifier arranged to power a first conversion sensor and a second conversion sensor with a given polarity regardless of whether the input has a positive or negative polarity. The sensor also includes a semiconductor multiplexer circuit arranged to direct the first output to a common output port if the input has a positive polarity and direct the second output to the common output port if the input has a negative polarity. The polarity insensitive Hall Effect sensor provides an output representing a position without requiring a input polarity.
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17. An apparatus for a linear or rotation sensor, comprising:
means for producing a first output responsive to a given input;
means for producing a second output responsive to the given input, a sum of the first output and second output being constant regardless of whether the given input has a positive or negative polarity;
means for powering a first conversion sensor and a second conversion sensor with a given polarity regardless of whether the given input has a positive or negative polarity; and
means for directing the first output to a common output port if the given input has a positive polarity and directing the second output to the common output port if the given input has a negative polarity.
9. A method of sensing linear position or rotation, the method comprising:
producing a first output responsive to a given input at a first conversion sensor;
producing a second output responsive to the given input at a second conversion sensor, a sum of the first output and second outputs being constant regardless of whether the given input has positive or negative polarity;
powering, at a semiconductor rectifier, the first conversion sensor and the second conversion sensor with a given polarity regardless of whether the given input has a positive or negative polarity; and
directing, at a semiconductor multiplexer circuit, the first output to a common output port if the given input has a positive polarity and the second output to the common output port if the given input has a negative polarity.
1. A linear or rotation sensor, comprising:
a first conversion sensor configured to produce a first output responsive to a given input;
a second conversion sensor configured to produce a second output responsive to the given input, a sum of the first output and second outputs being constant regardless of whether the given input has a positive or negative polarity;
a semiconductor rectifier arranged to power the first conversion sensor and the second conversion sensor with a given polarity regardless of whether the given input has a positive or negative polarity; and
a semiconductor multiplexer circuit arranged to direct the first output to a common output port if the given input has a positive polarity and direct the second output to the common output port if the given input has a negative polarity.
2. The sensor of
3. The sensor of
a first channel to direct the first output to the common output port, the first channel including a first set of n-type MOSFET semiconductors connected in series and a second set of p-type MOSFET semiconductors connected in series, the first set and the second set connected in parallel; and
a second channel to direct the second output to the common output port, the second channel including a third set of n-type MOSFET semiconductors connected in series and a fourth set of p-type MOSFET semiconductors connected in series, the third set and the fourth set connected in parallel.
4. The sensor of
respective sources of the MOSFETs within the respective first, second, third, and fourth sets of semiconductors are directly connected, respective gates of the MOSFETs of the first, second, third, and fourth sets of semiconductors are directly connected,
a first drain of the MOSFETs of the first set and a first drain of the MOSFETs of the second set are coupled to receive the first output,
the gates of the MOSFETs of the first set and the fourth set are coupled to a first input port receiving a first signal defining a first portion of the given input,
the gates of the MOSFETs of the second set and the third set are coupled to a second input port receiving a second signal defining a second portion of the given input, the first and second signals, when measured relative to each other at same time instants to determining the polarity of the given input,
a first drain of the MOSFETs of the third set and a first drain of the MOSFETs of the fourth set are coupled to receive the second output, and
a second drain of the MOSFETs of the first set, a second drain of the MOSFETs of the second set, a second drain of the MOSFETs of the third set, and a second drain of the MOSFETs of the fourth set are coupled to the common output port.
5. The sensor of
a first MOSFET of the at least four MOSFETs is coupled (i) at its drain to a first port of the given input and a drain of a second MOSFET of the at least four MOSFETs, (ii) at its gate to a second port of the given input, and (iii) at its source to the source of a third MOSFET of the at least four MOSFETs and the first and second conversion sensors,
the second MOSFET of the at least four MOSFETs is coupled (i) at its drain to the first port of the given input and the drain of the first MOSFET, (iii) at its gate to a second port of the given input, and (iii) at its source to the source of a fourth MOSFET of the at least four MOSFETs and the first and second conversion sensors,
the third MOSFET of the at least four MOSFETs is coupled (i) at its source to the source of the first MOSFET, and the first and second conversion sensors, (ii) at its drain to the second port of the given input, and (iii) at its gate to the first port if the given input, and
the fourth MOSFET is coupled (i) at its drain to the second port of the given input and the drain of the third MOSFET, (ii) at its gate to the first port of the given input, and (iii) at its source to the source of the second MOSFET and the first and second conversion sensors.
6. The sensor of
7. The sensor of
8. The sensor of
10. The method of
11. The method of
directing, in a first channel of the semiconductor multiplexer, the first output to the common output port, the first channel including a first set of n-type MOSFET semiconductors connected in series and a second set of p-type MOSFET semiconductors connected in series, the first set and the second set connected in parallel; and
directing, in a second channel of the semiconductor multiplexer, the second output to the common output port, the second channel including a third set of n-type MOSFET semiconductors connected in series and a fourth set of p-type MOSFET semiconductors connected in series, the third set and the fourth set connected in parallel.
12. The method of
directly connecting respective sources of the MOSFETs within the respective first, second, third, and fourth sets of semiconductors;
directly connecting gates of MOSFETs within the respective first, second, third, and fourth sets of semiconductors;
coupling a first drain of the MOSFETs of the first set and a first drain of the MOSFETs of the second set to receive the first output,
coupling gates of the first set and the fourth set to a first input port receiving a first signal defining a first portion of the given input,
coupling gates of the second set and the third set to a second input port receiving a second signal defining a second portion of the given input, the first and second signals, when measured relative to each other at same time instants determine the polarity of the given input,
coupling a first drain of the MOSFETs of the third set and a first drain of the MOSFETs of the fourth set to receive the second output, and
coupling a second drain of the MOSFETs of the first set, a second drain of the MOSFETs of the second set, a second drain of the MOSFETs of the third set, a second drain of the MOSFETs of the fourth set to the common output port.
13. The method of
coupling a first of the MOSFETs (i) at its drain to a first port of the given input and a drain of a second of the MOSFETs, (ii) at its gate a second port of the given input, and (iii) at its source to the source of a third of the MOSFETs and the first and second conversion sensors,
coupling the second of the MOSFETs (i) at its drain to the first port of the given input and the drain of the first of the MOSFETs, (ii) at its gate to a second port of the given input, and (ii) at its source to the source of a fourth of the MOSFETs and the first and second conversion sensors,
coupling the third of the MOSFETs (i) at its source to the source of the first of the MOSFETs, and the first and second conversion sensors, (ii) at its drain to the second port of the given input, and (iii) at its gate to the first port if the given input, and
coupling the fourth of the MOSFETs (i) at its drain to the second port of the given input and the drain of the third of the MOSFETs, (ii) at its gate the first port of the given input, and (iii) at its source to the source of the second of the MOSFETs and the first and second conversion sensors.
14. The method of
directing, at the semiconductor rectifier, a signal of a correct polarity to the first conversion sensor and the second conversion sensor based the polarity of the given input; and
directing, the semiconductor multiplexer, based on the polarity of the given input, first output or the second output to the common output port.
15. The method of
programming the first and second conversion sensors using a programming module having three ports through which to program the first and second conversion sensors by: coupling first and second programming module ports to the semiconductor rectifier to power the first and second conversion sensors during application of positive and negative polarity voltage levels, respectively, and coupling a third programming module port to the common output to program the first and second conversion sensors during application of the positive and negative polarity voltage levels, respectively, to the first and second conversion sensors.
16. The method of
18. The means of
19. The means of
first means for directing the first output to the common output port, the first means including a first set of n-type MOSFET semiconductors connected in series and a second set of p-type MOSFET semiconductors connected in series, the first set and the second set connected in parallel; and
second means for directing the second output to the common output port, the second means including a third set of n-type MOSFET semiconductors connected in series and a fourth set of p-type MOSFET semiconductors connected in series, the third set and the fourth set connected in parallel.
20. The means of
respective sources of the MOSFETs within the respective first, second, third, and fourth sets of semiconductors are directly connected, gates of MOSFETS within the respective the first, second, third, and fourth sets of semiconductors are directly connected,
a first drain of the MOSFETs of the first set and a first drain of the MOSFETs of the second set are coupled to receive the first output,
gates of the first set and the fourth set are coupled to a first input port receiving a first signal defining a first portion of the given input,
gates of the second set and the third set are coupled to a second input port receiving a second signal defining a second portion of the given input, the first and second signals, when measured relative to each other at same time instants determine the polarity of the given input,
a first drain of the MOSFETs of the third set and a first drain of the MOSFETs of the fourth set are coupled to receive the second output, and
a second drain of the MOSFETs of the first set, a second drain of the MOSFETs of the second set, a second of the drains of the third set, a second of the drains of the fourth set are coupled to the common output port.
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Potentiometers have a physical contact that rides on a resistive element. The physical contact of the potentiometer is a point of failure for the potentiometer. This point of failure decreases the reliability of potentiometers in relation to non-contacting sensors, such as a Hall Effect sensor. Non-contacting sensors, such as Hall Effect sensors, can replace potentiometers in many applications.
In an embodiment, a linear or rotation sensor includes a first conversion sensor configured to produce a first output responsive to a given input. The sensor further includes a second conversion sensor configured to produce a second output responsive to the given input. The sum of the first output and second outputs is constant regardless of whether the given input has a positive or negative polarity. The sensor also includes a semiconductor rectifier arranged to power the first conversion sensor and the second conversion sensor with a given polarity regardless of whether the given input has a positive or negative polarity. The sensor also includes a semiconductor multiplexer circuit arranged to direct the first output to a common output port if the given input has a positive polarity and direct the second output to the common output port if the given input has a negative polarity.
In an embodiment, the first conversion sensor is a hall effect sensor and the second conversion sensor is a hall effect sensor.
In an embodiment, the semiconductor multiplexer can include a first channel to direct the first output to the common output port. The first channel includes a first set of n-type MOSFET semiconductors connected in series and a second set of p-type MOSFET semiconductors connected in series. The first set and the second set are connected in parallel. The semiconductor multiplexer includes a second channel to direct the second output to the common output port. The second channel includes a third set of n-type MOSFET semiconductors connected in series and a fourth set of p-type MOSFET semiconductors connected in series. The third set and the fourth set are connected in parallel.
In an embodiment, respective sources of the MOSFETs within the respective first, second, third, and fourth sets of semiconductors are directly connected. The respective gates of the MOSFETs of the first, second, third, and fourth sets of semiconductors are directly connected. A first of the drains of the first set and a first of the drains of the second set are coupled to receive the first output. The gates of the first set and the fourth set are coupled to a first input port receiving a first signal defining a first portion of the given input. The gates of the second set and the third set are coupled to a second input port receiving a second signal defining a second portion of the given input. The first and second signals, when measured relative to each other at the same time instants, determine the polarity of the given input signal. A first of the drains of the third set and a first of the drains of the fourth set are coupled to receive the second output. A second of the drains of the first set, a second of the drains of the second set, a second of the drains of the third set, and a second of the drains of the fourth set are coupled to the common output port.
In an embodiment, the semiconductor rectifier includes at least four MOSFETs. Each MOSFET has a respective source, drain, and gate. A first of the MOSFETs is coupled (i) at its drain to a first port of the given input and a drain of a second of the MOSFETs, (ii) at its gate to a second port of the given input, and (iii) at its source to a the source of third of the MOSFETs and the first and second conversion sensors. The second of the MOSFETs is coupled (i) at its drain to the first port of the given input and the drain of the first of the MOSFETs, (iii) at its gate to a second port of the given input, and (iii) at its source the source of to a fourth of the MOSFETs and the first and second conversion sensors. The third of the MOSFETs is coupled (i) at its source to the source of the first of the MOSFETs, and the first and second conversion sensors, (ii) at its drain to the second port of the given input, and (iii) at its gate to the first port if the given input. The fourth of the MOSFETs is coupled (i) at its drain to the second port of the given input and the drain of the third of the MOSFETs, (ii) at its gate to the first port of the given input, and (iii) at its source to the source of the second MOSFETs and the first and second conversion sensors.
In an embodiment, the semiconductor rectifier is configured to direct a signal of a correct polarity to the first conversion sensor and the second conversion sensor based on the polarity of the given input. The semiconductor multiplexer, based on the polarity of the same given input, is configured to direct the first output or the second output to the common output port.
In an embodiment, the sensor also includes a programming module including three ports through which to program the first and second conversion sensors. The first and second programming module ports are coupled to the semiconductor rectifier to power the first and second conversion sensors during application of positive and negative polarity voltage levels, respectively. The third programming module port is coupled to the common output to program the first and second conversion sensors during application of the positive and negative polarity voltage levels, respectively, to the first and second conversion sensors.
In an embodiment, the first and second conversion sensors are configured to measure a rotation or linear position of a mechanical device being observed regardless of the polarity of the given input.
In an embodiment, a method of sensing linear position or rotation includes producing a first output responsive to a given input at a first conversion sensor. The method further includes producing a second output responsive to the given input at a second conversion sensor. The sum of the first output and second outputs is constant regardless of whether the given input has positive or negative polarity. The method further includes powering, at a semiconductor rectifier, the first conversion sensor and the second conversion sensor with a given polarity regardless of whether the given input has a positive or negative polarity. The method also includes directing, at a semiconductor multiplexer circuit, the first output to a common output port if the given input has a positive polarity and the second output to the common output port if the given input has a negative polarity.
In an embodiment, an apparatus for linear or rotation sensor includes a first conversion sensor means for producing a first output responsive to a given input. The apparatus further includes a second conversion sensor means for producing a second output responsive to the given input. The sum of the first output and second output is constant regardless of whether the given input has a positive or negative polarity. The apparatus further includes a semiconductor rectifier means for powering the first conversion sensor and the second conversion with a given polarity regardless of whether the given input has a positive or negative polarity. The apparatus also includes a semiconductor multiplexer means for directing the first output to a common output port if the given input has a positive polarity and direct the second output to the common output port if the given input has a negative polarity.
The foregoing will be apparent from the following more particular description of example embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating embodiments of the present invention.
A description of example embodiments of the invention follows.
A semiconductor rectifier 410 is coupled to a first input port 402 and a second input port 404, receiving voltages of V1 and V2, respectively. The semiconductor rectifier 410 is coupled to output to a first conversion sensor 412 and second conversion sensor 414, which can both be Hall Effect sensors, or other polarity sensitive sensors. The semiconductor rectifier 410 is configured to output a positive polarity to both the first conversion sensor 412 and second conversion sensor 414, regardless of the polarity of the first input port 402 and second input port 404. In other words, the semiconductor rectifier provides a voltage difference of |V1−V2| to both the first conversion sensor 412 and second conversion sensor 414. Therefore, the first conversion sensor 412 and second conversion sensor 414 can output respective working signals, being Out1 and Out2, respectively, to a semiconductor multiplexer circuit 416. The semiconductor multiplexer circuit 416 is configured to determine the polarity of the first input port 402 and second input port 404 (e.g., |V1−V2|) and output either Out1 or Out2 at the output port 406 based on the determined polarity.
Therefore, the polarity insensitive Hall Effect sensor can receive a positive or negative power on either its first input port 402 or second input port 404. An individual Hall Effect sensor, such as the Hall Effect sensor 308 shown in
In reference to
MOSFET transistor elements Q1, Q2, Q3 and Q4 rectify the POWER1 and POWER2 signals. In an embodiment, Q1 and Q3 are N-channel MOSFETs and Q2 and Q4 are P-channel MOSFETs. The semiconductor rectifier 510 is coupled to provide a correct polarity to the first conversion sensor 512 and second conversion sensor 514 at their Vdd1 and Vss1 and Vdd2 and Vss2 ports, respectively. A capacitor C1 maintains a voltage difference between the two outputs of the semiconductor rectifier 510. Capacitors C2 and C3 further maintain a voltage difference between one of the outputs of the semiconductor rectifiers and the first conversion sensor 512 and second conversion sensor 514.
The first conversion sensor 512 provides an output to the semiconductor multiplexer circuit 516 and the second conversion sensor 514 provides an output to the semiconductor multiplexer circuit 516. The semiconductor multiplexer circuit 516 also accepts POWER1 and POWER2 as inputs. Based on the relationship of POWER1 and POWER2, the semiconductor multiplexer circuit 516 outputs either the output of the first conversion sensor 512 or the output of the second multiplexer circuit 516 at the output port 506.
Q1, Q2, Q3, and Q4 are selected so that the sum of gate threshold voltages of the N and P channel MOSFETs is less than the applied voltage. The Q1, Q2, Q3, and Q4 MOSFETs of the semiconductor rectifier 510 route the positive voltage applied to the Vdd1 and Vdd2 pins of the first conversion sensor 512 and second conversion sensor 514 (e.g., Hall Effect sensors), respectively. The Q1, Q2, Q3, and Q4 MOSFETs of the semiconductor rectifier 510 route the negative voltage to the Vss1 and Vss2 pins of the first conversion sensor 512 and second conversion sensor 514, respectively.
The first conversion sensor 512 outputs a signal at Out1 (Port 15) as Power1 Output Path 612 and the second conversion sensor 514 outputs a signal at Out2 (port 7) as Power2 Output Path 632. The semiconductor multiplexer circuit 516 (e.g., a switch matrix) routes one of the two outputs, Out1 and Out2 of the first conversion sensor 512 and second conversion sensor 514, respectively, to the output port 606. The semiconductor multiplexer circuit 516 is comprised of MOSFETs Q5, Q6, Q7, Q8, Q9, Q10, Q11 and Q12. In an embodiment, the MOSFETs Q5-Q12 are MOSFET pair IRF7343 devices, however other MOSFETs can be used. When positive voltage is applied to POWER1 and relative negative power to POWER2, Q5, Q6, Q7, and Q8 (a first channel) are turned on while Q9, Q10, Q11 and Q12 (a second channel) are in cutoff. The current runs through Q5, Q6, Q7, and Q8 (the first channel) to output port 606 along Power1 Output Path 612. Even though both the first conversion sensor 512 and second conversion sensor 514 are powered by the POWER1 current path 610b, only Out1 of the first conversion sensor 512 is outputted at the output port 606.
When a positive voltage is applied to POWER2 relative to POWER1, MOSFETs Q9, Q10, Q11 and Q12 (the second channel) are turned on and Q5, Q6, Q7 and Q8 (the first channel) are turned off/in cutoff. The current runs through Q9, Q10, Q11 and Q12 (the second channel) to output port 606 along Power2 Output Path 632. Even though both the first conversion sensor 512 and second conversion sensor 514 are powered by the POWER2 current path 630a, only Out2 of the second conversion sensor 514 is outputted at the output port 606.
A person of ordinary skill in the art can recognize that regardless of the polarity of POWER1 and POWER2, that POWER1 current path 610a-b and POWER2 current path 630a-b flow through Vdd1, Vss1 and Vdd2, Vss2 simultaneously, respectively. However,
Pairs of MOSFETs Q5 and Q6, Q7 and Q8, (the first channel) Q9 and Q10, and Q11 and Q12 (the second channel) are coupled at each pair's respective MOSFET source port such that the body diode of the opposing channel MOSFET does not conduct current. Further, each channel needs a set of N-channel MOSFETs and a set of P-channel MOSFETs because neither an N-channel MOSFET nor a P-channel MOSFET alone can conduct over the full range of output voltages for the polarity insensitive Hall Effect sensor. For example, when POWER1 is positive (e.g., 5V) relative to POWER2, the gates of Q5 and Q6 are at 5V, and Q5 and Q6 are turned on for output voltages from 0 to about 4V. Above 4V, there is no longer sufficient gate-source voltage to keep the MOSFET on. Likewise, P-channel MOSFETs Q7 and Q8 are turned on when the output voltage is between 1V and 5V, but for voltages below 1V, there is insufficient gate-source voltage to keep them on. For much of the range, both the N-channel and P-channel MOSFETs pairs are active but at the extremes of the range, only one or the other is turned on. Likewise, the combined output at the Output Port 606 is the combination of the current through MOSFET pairs Q5 and Q6 and Q7 and Q8. Although the output impedance varies, typical current draw in most applications is small, so the voltage drop in the semiconductor multiplex has a minimal variance in the voltage drop.
The resistance at saturation (Rds) of the MOSFETS determines the voltage drop through the MOSFETs. One example MOSFET that can be used is the IRF7343, which has 50 mΩ and 105 mΩ Rds for the N- and P-channel MOSFETs, respectively. These Hall Effect sensors consume current of approximately 16 milliamps (mA), which causes a voltage drop through the MOSFETS of about 2.48 mV. The voltage applied powers two Hall Effect sensors, for example an MLX90316, which houses two separate Hall Effect sensor dies in one package.
Potentiometers and their Hall Effect sensor equivalents can change their output linearly as the rotational position they are detecting changes. Output1 702 shows the output of the polarity insensitive Hall Effect sensor in a first polarity. Output2 704, the complimentary output to Output1 702, should therefore an increase in voltage from the negative supply that is the same as the voltage decrease that Output1 702 has from the positive supply. For example, if the input shaft of the hall sensor is at 90°, Output1 702 produces a signal representing 25% of the positive supply, and Output2 704 produces a signal representing 75% of the positive supply, or 25% away from the negative supply.
In an embodiment, the invention also solves a problem created when using the two Hall Effect sensors. Each Hall Effect sensor is programmed, for example by a Melexis PTC-04 programming box. Programming a Hall Effect sensor is performed by connecting to three wires of the sensor. However, two Hall Effect sensors share the three wires. The circuit of the present invention solves this problem. To program the first hall sensor, the three programming wires are connected to the polarity insensitive Hall Effect Sensor. To program the second sensor, the power and ground wires are reversed and a second sensor can then be programmed. The programming box can access only one of the two sensors at a time because the switching elements behave different depending on how power is applied. The polarity insensitive Hall Effect sensor allows power reversal and therefore provides a way of programming two Hall sensors through a single wire interface.
Other structures of the polarity insensitive Hall Effect circuit can be designed by a variety of electrical devices and connections.
“Polarity protection implemented with a MOSFET” by Jokinen, U.S. Pat. No. 7,126,801 (hereinafter “Jokinen”) shows an N-channel MOSFET in series with a negative lead to disconnect in case of reverse polarity. “Input Power Protected Ratiometric Output Sensor Circuit” by Lin, U.S. Pat. No. 7,453,268 shows a system for a ratiometric sensor using both high side and low side MOSFET switches. “Reverse Voltage Protection Circuit” by Zhang, U.S. Pub. No. 2011/0195744 (hereinafter “Zhang”) and “Integrated overvoltage and reverse voltage protection circuit” by Laraia, U.S. Pub. No. 2004/0052022 (hereinafter “Laraia”) show similar methods. However, Jokinen, Lin, Zhang and Laraia do not suggest operation while reverse voltage is applied.
“Polarity Detection Circuit” by Terasaki, Japanese Pat. No. JP02148955 (hereinafter “Terasaki”) shows a system for detecting reverse polarity, but employs a diode bridge for rectification, which results in an undesirable high voltage drop across the diode bridge. The present invention avoids such a voltage drop.
The above patents and patent applications are hereby incorporated by reference in their entirety.
In another embodiment, instead of using two separate Hall Effect sensors, the polarity insensitive Hall Effect sensor can couple an amplifier to a single Hall Effect sensor to provide an inversed output graph with a negative transformation (e.g., the relationship of Vout=Vsupply−Vin when polarity is reversed). Using only one Hall Effect sensor reduces cost and requires programming of only one Hall Effect sensor. However, the output when the polarity is reversed may have a larger error because the amplifier's error is added to the Hall Effect error. When using two Hall Effect sensors, only one sensor is active at a time so only the error from one sensor is present.
Other elements could be used as substitutes for the MOSFET transistors (e.g., relays or other devices) as long as they have high off state resistance and low voltage drop in the on state.
The teachings of all patents, published applications and references cited herein are incorporated by reference in their entirety.
While this invention has been particularly shown and described with references to example embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
Patent | Priority | Assignee | Title |
11761985, | Feb 09 2021 | Analog Devices International Unlimited Company | Calibration using flipped sensor for highly dynamic system |
Patent | Priority | Assignee | Title |
4139880, | Oct 03 1977 | Motorola, Inc. | CMOS polarity reversal circuit |
5712560, | Sep 01 1994 | Kabushiki Kaisha Toshiba | Drive speed detector for a motor that drives a data reproducing device |
6166451, | Jan 14 1999 | SHENZHEN XINGUODU TECHNOLOGY CO , LTD | Distributed airbag firing system and interface circuit therefor |
7126801, | Dec 17 2001 | CORIANT OY | Polarity protection implemented with a MOSFET |
7453268, | Jun 29 2005 | Delphi Technologies, Inc. | Input power protected ratiometric output sensor circuit |
8120884, | Feb 09 2010 | Texas Instruments Incorporated | Reverse voltage protection circuit |
20020060889, | |||
20040052022, | |||
20110195744, | |||
JP2148955, |
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